I am seeing an intermittent failure of the call and I'm trying to understand what could be causing it to fail. My code always calls it with the same three constant values, so I don't think it is related to the inputs. I'm wondering if it might be a hardware problem or maybe a race condition of some kind. So far I have only seen it on one device so that also makes me think it might be hardware related.
My code calls system_rtc_mem_read() after a deep sleep to restore state. My next step will be to see if I can reproduce it with a simple test case but I wanted to check if anyone had any experience with this condition first.
Any insight would be greatly appreciated.